Vented screwcap closure with diffusive membrane liner

ABSTRACT

A liner for a wine bottle cap is constructed such that a gas, such as oxygen, that diffuses through the liner moves along a path within the liner whose length is greater than the thickness of the liner. In this manner, oxygen from the atmospheric air can diffuse through a relatively thin liner at a slow rate before reaching the bottled wine. The liner is comprised of alternating layers of material semi-permeable to oxygen and material impermeable to oxygen, the impermeable layers containing open areas through which oxygen can diffuse. As oxygen diffuses through the alternating layers, the path(s) along which the oxygen diffuses is determined by the locations of the open areas in the impermeable layers. The liner may be assembled with a screw cap closure that comprises ventilation holes connected by a raceway for distribution of atmospheric air to the liner.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority from U.S. Provisional Patent Application No. 61/036,043, filed Mar. 12, 2008 and U.S. Provisional Patent Application No. 61/107,992, filed Oct. 23, 2008, the contents of which are incorporated herein by reference in its entirety.

FIELD OF THE INVENTION

The present invention relates generally to closures for bottles. More particularly, the invention relates to screw cap closures with oxygen permeability characteristics for wine bottles.

BACKGROUND OF THE INVENTION

Alongside winemaking, wine bottling technology has evolved over the past several hundred years. The winemaking industry has relied on the use of cork, which allows small amounts of oxygen through, as a sealing medium for wine bottles in the wine aging process. Oxygen that permeates through a wine bottle's cork seal is “consumed” by the bottled wine through the formation of acetaldehyde, which serves as a linking molecule between monomers. This process helps to stabilize longer chains of tannins, resulting in a smoother tasting wine over time.

The use of cork as a wine bottle sealing medium, however, suffers from several deficiencies. For one thing, the variability in natural cork bark, from which cork is made, results in variability in the rate of oxidation of wines in different bottles and consequently, variability in taste across bottles. In addition, cork contains a chemical known as 2,4,6 tricholoroanisole (TCA), a product of fungi that live in natural cork. When 2,4,6 TCA is released into wine, an unwelcome aroma is created. In small amounts, 2,4,6 TCA mutes the wine's aromatics but may completely ruin the wine in larger amounts. Excessive release of 2,4,6 TCA affects 2% to 5% of all corks. Furthermore, cork suffers from structural defects that include crumbling, breaking, and seepage, and requires the use of a tool (e.g., corkscrew) for removal from the wine bottle. Moreover, it is difficult to reseal a cork-sealed wine bottle without the use of additional devices.

Several attempts have been made to introduce wine bottle closure products that aim to rectify some or all of the above deficiencies. These products include: synthetic cork, screw caps, Vino-Lock (a glass stopper with a silicone seal), Zork (a peel-off plastic closure), and others. None of these products, however, have eliminated all of the above deficiencies. For example, while synthetic corks can be made to provide a steady and customizable amount of oxygen flow into a wine bottle, a synthetic cork with an oxygen transfer rate similar to that of cork would use a material so hard that excessive force would be needed to remove it from the wine bottle neck. Screw caps, on the other hand, let in too little oxygen into the bottle.

Thus, there remains a need in the art for a screw cap closure with oxygen permeability characteristics suitable for packaging wine.

SUMMARY OF THE INVENTION

According to one aspect of the present invention, a liner for a wine bottle cap is constructed such that a gas, such as oxygen, that diffuses through the liner moves along a path within the liner whose length is greater than the thickness of the liner. In this manner, oxygen from the atmospheric air can diffuse through a relatively thin liner at a slow rate before reaching the bottled wine. In one approach, the liner is comprised of alternating layers of material semi-permeable to oxygen and material impermeable to oxygen, the impermeable layers containing open areas through which oxygen can diffuse. As oxygen diffuses through the alternating layers, the path(s) along which the oxygen diffuses is determined by the locations of the open areas in the impermeable layers. In this approach, therefore, liners with varying rates of oxygen diffusion may be created by designing and selecting the geometries of the liner layers to create diffusion paths of varying lengths.

According to another aspect of the present invention, a liner for a wine bottle cap is constructed such that the thickness of the liner at the center of the liner is greater than the thickness of the liner at the periphery of the liner, the liner being made of material that is semi-permeable to the gas. In this manner, oxygen from the air can diffuse through the liner at a slow rate due to the thickness of the liner in the center, while the liner is still relatively thin along the periphery, where the liner serves as a contact surface between the wine bottle cap and the rim of the wine bottle.

According to another aspect of the present invention, a screw cap closure for a wine bottle is constructed to comprise a plurality of ventilation holes that are connected by one or more raceways. The ventilation holes allow atmospheric air to pass through the screw cap closure top to reach and eventually diffuse through a liner inside the screw cap closure the raceway allows even distribution of air to all parts of the liner even when the screw cap closure and the liner are not precisely aligned.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other aspects and features of the present invention will become apparent to those ordinarily skilled in the art upon review of the following description of specific embodiments of the invention in conjunction with the accompanying figures, wherein:

FIG. 1 illustrates a cross section of an exemplary assembled bottle cap and liner.

FIG. 2 illustrates a cross section of an exemplary multi-layer liner.

FIG. 3 illustrates a top view of the multiple layers of an exemplary multi-layer liner.

FIG. 4 illustrates sheets for constructing the multiple layers of an exemplary multi-layer liner.

FIG. 5 illustrates multiple layers of an exemplary multi-layer liner.

FIG. 6 illustrates multiple layers of an exemplary multi-layer liner.

FIG. 7 illustrates an exemplary liner that is thicker in the middle than in the periphery.

FIGS. 8A and 8B illustrate an exemplary screw cap closure.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention will now be described in detail with reference to the drawings, which are provided as illustrative examples of the invention so as to enable those skilled in the art to practice the invention. Notably, the figures and examples below are not meant to limit the scope of the present invention to a single embodiment, but other embodiments are possible by way of interchange of some or all of the described or illustrated elements. Moreover, where certain elements of the present invention can be partially or fully implemented using known components, only those portions of such known components that are necessary for an understanding of the present invention will be described, and detailed descriptions of other portions of such known components will be omitted so as not to obscure the invention. In the present specification, an embodiment showing a singular component should not be considered limiting; rather, the invention is intended to encompass other embodiments including a plurality of the same component, and vice-versa, unless explicitly stated otherwise herein. Moreover, applicants do not intend for any term in the specification or claims to be ascribed an uncommon or special meaning unless explicitly set forth as such. Further, the present invention encompasses present and future known equivalents to the known components referred to herein by way of illustration. Still further, the drawings are provided for illustration and not limitation or exact reproduction of embodiments of the invention, and they are not necessarily to scale.

According to one approach, a liner for a wine bottle cap is constructed such that a gas such as oxygen, that diffuses through the liner moves along a path within the liner whose length is greater than the thickness of the liner. In this manner, a gas such as oxygen from the atmospheric air can diffuse through a relatively thin liner at a slow rate before reaching the bottled wine. FIG. 1 depicts a cross section of an assembled wine bottle cap 102 and liner 104. Liner 104 is located within the wine bottle cap 102 and is adjacent to the lower surface of the wine bottle cap's top 106. Wine bottle cap 102 may be constructed from metal such as aluminum or steel that are impermeable to atmospheric air, and contains one or more openings, or ventilation holes, through which atmospheric air can pass to reach liner 104. In one embodiment, wine bottle cap 102 is a screw cap closure. It should be noted, however, that other embodiments of the present invention may include liners that are fitted within bottle cap closures other than screw cap closures and bottle cap closures for bottles other than wine bottles.

According to one approach, a liner for a wine bottle cap, such as liner 104 in FIG. 1, comprises two or more layers that include at least one semi-permeable layer and at least one impermeable layer. Semi-permeable layers are constructed from materials that are semi-permeable to oxygen such that oxygen can diffuse through the semi-permeable layers. An example of a material that is semi-permeable to oxygen is polyethylene. Material for semi-permeable layers may also be slightly elastic so that the semi-permeable layers may be compressed in the areas where the liner is sandwiched between the rim of the bottle below and the screw cap closure above. This elasticity fills any irregularities in the sealing surface and ensures a tight seal for the bottle.

Materials impermeable to oxygen include aluminum foil and tin. The liner may further comprise layers that are permeable to oxygen, such as a food-grade polymer such as polyvinyl dichloride (e.g., Saran). These permeable materials allow small amounts of oxygen to diffuse through them whereas non permeable layers effectively allow no oxygen to permeate through. In one embodiment, the top and bottom layers of the liner comprise permeable layers that are constructed from food-grade material. In an alternative embodiment where the impermeable layers are constructed from food-grade material, the liner contains no top and bottom permeable layers. Although the descriptions here of semi-permeable and impermeable layers focus on whether the layers are permeable to oxygen, it will be appreciated that other embodiments of the present invention may employ liner layers that are semi-permeable or impermeable to other gases.

The liner may be constructed such that successive layers alternate between a permeable or semi-permeable layer and an impermeable layer. FIG. 2 illustrates a cross section of an assembled liner 200 that includes five layers 202, 204, 206, 208, and 210. Layers 202 and 210 are permeable to oxygen, layer 206 is semi-permeable to oxygen, and layers 204 and 208 are impermeable to oxygen. As FIG. 2 illustrates, liner 200 comprises successive layers that alternate between a permeable or semi-permeable layer (i.e., layers 202, 206, and 208) and an impermeable layer (i.e., layers 204 and 208). According to one embodiment, the liner's impermeable layers comprise one or more apertures through which oxygen is allowed to pass through. For example, impermeable layer 204 in liner 200 contains apertures 212, and impermeable layer 208 similarly contains apertures 214. As a result, oxygen diffusing through a liner passes through the entire surface areas of the liner's permeable layers and semi-permeable layers and the apertures of the liner's impermeable layers. In the example illustrated in FIG. 2, oxygen that diffuses through liner 200 from top to bottom passes through the entirety of permeable layer 202, the apertures 212 of impermeable layer 206, the entirety of semi-permeable layer 206, the apertures 214 of impermeable layer 208, and finally, the entirety of permeable layer 210.

Because oxygen cannot pass through the entire surface areas of impermeable layers and can only pass through the apertures of the impermeable layers, oxygen diffusing through a liner is forced to diffuse along paths, within permeable or semi-permeable layers sandwiched between two impermeable layers, that connect the apertures of the two impermeable layers. As a result, oxygen diffusing through the liner is forced to travel a longer distance, thereby achieving a slow oxygen diffusion rate even for relatively thin liners. Referring to the example illustrated in FIG. 2, oxygen diffusing through liner 200 from top to bottom diffuses through layers 204, 206, and 208, in that order. Semi-permeable layer 206 is sandwiched between impermeable layers 206 and 208. Oxygen enters semi-permeable layer 206 through the apertures 212 in impermeable layer 204. However, the oxygen in semi-permeable layer 206 can exit only through the apertures 214 in impermeable layer 208. As a result, oxygen in semi-permeable layer 206 is forced to travel along a path that is at least as long as path length PL.

Generally, when the locations of apertures in the two sandwiching impermeable layers (e.g., layers 204 and 208) are different, oxygen diffusing through the sandwiched permeable or semi-permeable layer (e.g., layer 206) will be forced to travel some distance before being able to leave the sandwiched permeable or semi-permeable layer. When oxygen diffuses through a liner vertically (i.e., enters the liner from the top and exits the liner from the bottom), as is the case with liners encased in bottle caps such that the sides of the liners are adjacent to impermeable material such as metal, and oxygen enters from ventilation holes in the bottle cap near the top of the liner, there is horizontal diffusion of oxygen (e.g., for a distance of PL) in the permeable or semi-permeable layers that are sandwiched between two impermeable layers.

According to one approach, liner 200 is constructed such that path length PL is greater than the thickness of liner 200. In another approach, path length PL may be smaller than the thickness of liner 200, but liner 200 may additionally include more layers such that the total amount of distance traveled by oxygen diffusing through liner 200 is greater than the thickness of liner 200.

According to one approach, the impermeable layers of a liner include a plurality of perforations, the location of the perforations being different between successive impermeable layers. For example, FIG. 3 depicts a top view of the multiple layers of an assembled liner that includes five layers 302, 304, 306, 308, and 310. Layers 302, 304, 306, 308, and 310 may correspond to layers 202, 204, 206, 208, and 210 in FIG. 2. As depicted, the impermeable layers 304 and 308 each comprise a plurality of perforations 312 and 314, respectively, which are differently located on layers 304 and 308. Oxygen passing through the liner comprising the layers of FIG. 3 is thus required to travel at least a distance of PL within semi-permeable layer 306.

In one approach, the one or more impermeable layers of a liner are constructed from sheets of material that include a first strip area that contains a plurality of perforations and a second strip area that contains no perforations. For example, FIG. 4 depicts a sheet 404 that contains two strip areas containing perforations and three strips areas containing no perforations. Sheet 404 may be composed of aluminum foil or tin. An impermeable layer for a liner can be constructed by cutting sheet 402 into circular areas, such as circular area 412 and circular area 414. FIG. 4 additionally depicts sheet 408, which also has sheet areas containing perforations and sheet areas containing no perforations. As shown, sheet 408's perforations are located differently from the perforations on sheet 404. A same circular area, such as circular area 412, that is cut from both sheet 404 and sheet 408 results in two impermeable layers whose perforations are located differently from each other. Sheet 404 and sheet 408, when sandwiching a permeable or semi-permeable layer, force diffusing oxygen to travel some horizontal distance to traverse the layers, as described above.

FIG. 4 also depicts sheets 402, 406, and 408. Sheets 402 and 408 are sheets of permeable material and may be composed of a food-grade polymer, such as polyvinyl dichloride (e.g., Saran). Sheet 406 is a sheet of semi-permeable material and may be composed of polyethelene. As shown, sheets 402, 404, 406, 408, and 410 may be stacked and circular areas may be cut from the stack of sheets to construct the multiple layers of a liner, such as layers 302, 304, 306, 308, and 310 in FIG. 3.

According to one approach, the successive impermeable layers of a liner contain holes that are differently located. For example, a first impermeable layer may contain a single hole in the middle, and a second impermeable layer that is the next impermeable layer below may contain a number of holes (e.g., four holes) located along the periphery of the impermeable layer. A third impermeable layer that is the next impermeable layer below the second impermeable layer may contain a single hole in the middle again. Referring to FIG. 5, a liner is constructed from impermeable layer 502, semi-permeable layer 504, impermeable layer 506, semi-permeable layer 508, impermeable layer 510, and permeable layer 512. Impermeable layers 502, 506, and 510 are successive impermeable layers that contain hole(s) that are different from the impermeable layers immediately above or below. For example, impermeable layer 502 contains a single hole, impermeable layer 506 contains four holes located on a ring-shaped path along layer 506's periphery, and impermeable layer 510 also contains a single hole. In this geometry, oxygen diffusing from one impermeable layer to the next impermeable layer must travel at least a distance equal to the distance between a hole located in the middle of a layer (e.g., hole 514) to a hole located near the periphery of a layer (e.g., hole 516).

According to another approach, an impermeable layer sandwiched between two permeable or semi-permeable layers has a diameter that is smaller than the diameter of the liner, effectively resulting in the two permeable or semi-permeable layers contacting in an annular area through which oxygen may diffuse. FIG. 6 illustrates an example of this geometry. In FIG. 6, a liner is constructed from impermeable layer 602, semi-permeable layer 604, impermeable layer 606, semi-permeable layer 608, impermeable layer 610, and permeable layer 612. Impermeable layers 602 and 610 each contains a hole in the middle. Impermeable layer 606, however, has a diameter that is smaller than the diameters of semi-permeable layers 604 and 608, resulting in an annular contact area between layers 604 and 608 through which oxygen can diffuse. In this geometry, oxygen diffusing from one impermeable layer to the next impermeable layer must travel at least a distance equal to the distance between a hole located in the middle of a layer (e.g., hole 614) to the annular contact area between two semi-permeable layers resulting from the smaller diameter of a sandwiched impermeable layer.

According to another embodiment of the present invention, a liner for a wine bottle cap is constructed such that the thickness of the liner at the center of the liner is greater than the thickness of the liner at the periphery of the liner, the liner being made of material that is semi-permeable to the gas. In this manner, oxygen from the air can diffuse through the liner at a slow rate due to the thickness of the liner in the center, while the liner is still relatively thin along the periphery, where the liner serves as a contact surface between the wine bottle cap and the rim of the wine bottle. FIG. 7 illustrates an example liner 700 constructed such that the thickness of the liner 700 at the center of the liner is greater than the thickness of the liner 700 at the periphery. When liner 700 is assembled with a bottle cap that has a ventilation hole in the center, oxygen from atmospheric air diffuses through liner 700 along paths such as path 702 and path 704. The lengths of paths 702 and 704 are significantly greater than the thickness of liner 700 at the periphery. As a result, oxygen is able to diffuse through liner 700 at a slow rate while liner 700 maintains a relatively small thickness at the periphery that allows the liner to serve as a good contact surface between a wine bottle cap and the rim of a wine bottle.

As the above examples illustrate, the arrangement and geometry of semi-permeable and impermeable layers provide a mechanism through which the rate at which atmospheric gases (e.g., oxygen) diffuse through the liner and interact with the bottle contents (e.g., wine) can be regulated. For example, the positioning of holes and perforations can be varied to shorten or lengthen the distance that a gas travels horizontally within the liner, thereby increasing or decreasing the gas transmission rate. In the example illustrated in FIG. 4, the strip areas containing perforations may also be made wider or narrower to control the gas transmission rate. The strip areas containing perforations may be made so wide that there is effectively no horizontal diffusion of gas within the liner. In this case, the rate-limiting factor is the amount of aligned surface area between two successive impermeable layers.

By controlling the arrangement and geometry of the layers in the liner, a specific and precise rate of oxygen diffusion can be obtained. This is advantageous because different oxygen diffusion rates are optimal for different wines. For example, white wines require less oxygen than red wines. A liner may therefore be designed to provide an optimal oxygen diffusion rate for any bottled wine product.

According to one approach, a screw cap closure for a bottle is constructed to comprise a plurality of ventilation holes that are connected by one or more raceways. The ventilation holes allow atmospheric air to pass through the screw cap closure top to reach and eventually diffuse through a liner inside the screw cap closure. The raceway allows even distribution of air to all parts of the liner even when the screw cap closure and the liner is not precisely aligned. In one embodiment, the screw cap closure is assembled with the multi-layer liner described above.

FIGS. 8A and 8B illustrate an example of a screw cap closure comprising four ventilation holes that are connected by a raceway. FIG. 8A is a top-down view of the screw cap closure 800. Screw cap closure 800 contains ventilation holes 802 and raceway 804. FIG. 8B is a perspective illustration of screw cap closure 800. Atmospheric air passes through ventilation holes 802. Raceway 804 comprises an embossed channel such that atmospheric air that entered through ventilation holes 802 is distributed all along raceway 804. When screw cap 800 is assembled with a liner underneath, atmospheric air that entered through ventilation holes 802 is distributed along raceway 804 and reaches all parts of the top of the liner.

In other embodiments of the invention, screw cap closures may be constructed to contain ventilation holes and raceway geometries different from that depicted in FIGS. 8A and SB. For example, a screw cap closure may contain any number of ventilation holes located on a ring-shaped path along the periphery of the top of the screw cap closure.

Although the present invention has been particularly described with reference to the preferred embodiments thereof, it should be readily apparent to those of ordinary skill in the art that changes and modifications in the form and details may be made without departing from the spirit and scope of the invention. It is intended that the appended claims encompass such changes and modifications. 

1. A liner for a bottle cap constructed such that a gas passing through the liner moves along a path within the liner, the length of the path within the liner being greater than the thickness of the liner.
 2. The liner of claim 1, comprising a plurality of layers that includes one or more semi-permeable layers and one or more impermeable layers, the one or more semi-permeable layers being constructed of a material that is semi-permeable to the gas and the one or more impermeable layers being constructed of a material impermeable to the gas.
 3. The liner of claim 2, wherein layers within the plurality of layers alternate between a semi-permeable layer of the one or more semi-permeable layers and an impermeable layer of the one or more impermeable layers.
 4. The liner of claim 3, wherein each impermeable layer of the one or more impermeable layers comprises one or more apertures through which the gas is allowed to pass through.
 5. The liner of claim 4, wherein: the locations of the one or more apertures of a first impermeable layer, of the one or more impermeable layers, are different from the locations of the one or more apertures of a second impermeable layer, of the one or more impermeable layers; the second impermeable layer is immediately below a permeable layer, of the one or more permeable layers, that is immediately below the first impermeable layer.
 6. The liner of claim 5, wherein: the one or more apertures of the first impermeable layer comprise a hole located in the center of the first impermeable layer; and the one or more apertures of the second impermeable layer comprise a plurality of holes located on a ring-shaped path along the periphery of the second impermeable layer.
 7. The liner of claim 4, wherein the one or more impermeable layers are constructed from sheets of material that include a first strip area and a second strip area, the first strip area containing a plurality of perforations and the second strip area containing no perforations.
 8. The liner of claim 4, wherein the one or more impermeable layers are constructed from sheets of material that include a first strip area and a second strip areas the first strip area separated from the second strip area by a gap.
 9. The liner of claim 3, wherein; the plurality of layers includes an impermeable layer, of the one or more impermeable layers; the diameter of the impermeable layer is smaller than the diameter of a semi-permeable layer, of the one or more semi-permeable layers, immediately above the impermeable layer; and the diameter of the impermeable layer is smaller than the diameter of a semi-permeable layer, of the one or more semi-permeable layers, immediately below the impermeable layer.
 10. A liner for a bottle cap constructed such that the thickness of the liner at the center of the liner is greater than the thickness of the liner at the periphery of the liner.
 11. The liner of claim 10, comprising a single layer of material that is semi-permeable to the gas.
 12. A screw cap closure for a bottle that comprises a plurality of ventilation holes that are connected by at least one race way.
 13. The screw cap closure of claim 12, further comprising a liner constructed such that a gas passing through the liner moves along a path within the liner, the length of the path within the liner being greater than the thickness of the liner.
 14. The screw cap closure of claim 13, wherein the liner comprises a plurality of layers that includes one or more semi-permeable layers and one or more impermeable layers, the one or more semi-permeable layers being constructed of a material that is semi-permeable to the gas and the one or more impermeable layers being constructed of a material impermeable to the gas.
 15. The screw cap closure of claim 14, wherein layers within the plurality of layers alternate between a semi-permeable layer of the one or more semi-permeable layers and an impermeable layer of the one or more impermeable layers.
 16. The screw cap closure of claim 15, wherein each impermeable layer of the one or more impermeable layers comprises one or more apertures through which the gas is allowed to pass through.
 17. The screw cap closure of claim 16, wherein: the locations of the one or more apertures of a first impermeable layer, of the one or more impermeable layers, are different from the locations of the one or more apertures of a second impermeable layer, of the one or more impermeable layers; the second impermeable layer is immediately below a permeable layer, of the one or more permeable layers, that is immediately below the first impermeable layer.
 18. The screw cap closure of claim 15, wherein: the plurality of layers includes an impermeable layer, of the one or more impermeable layers; the diameter of the impermeable layer is smaller than the diameter of a semi-permeable layer, of the one or more semi-permeable layers, immediately above the impermeable layer; and the diameter of the impermeable layer is smaller than the diameter of a semi-permeable layer, of the one or more semi-permeable layers, immediately below the impermeable layer.
 19. The screw cap closure of claim 12, the plurality of ventilation holes located on a ring-shaped path along the periphery of the top of the screw cap closure.
 20. The screw cap closure of claim 12, wherein: the at least one raceway comprises an embossed channel; and at least part of the at least one raceway is not attached to the liner.
 21. A method for bottling wine in a bottle, comprising: closing the bottle with a screw cap closure that comprises a plurality of ventilation holes that are connected by at least one raceway.
 22. The method of claim 21, wherein the screw cap closure further comprises a liner constructed such that a gas passing through the liner moves along a path within the liner, the length of the path within the liner being greater than the thickness of the liner.
 23. A method for bottling wine in a bottle, comprising: closing the bottle with a cap closure that comprises a liner that is constructed such that a gas passing through the liner moves along a path within the liner, the length of the path within the liner being greater than the thickness of the liner 